Add 3 more bytes to a buffer to cover constants in string and null byte on top of 10 possible digits for an int.
Add 3 more bytes to a buffer to cover constants in string and null byte on top of 10 possible digits for an int.

Closes bug #1501223.

sk-/python2.7-type-annotator,sk-/python2.7-type-annotator,sk-/python2.7-type-annotator